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POST
/
api
/
v1
/
midi
/
generate
Generate MIDI from Audio
curl --request POST \
  --url https://apibox.erweima.ai/api/v1/midi/generate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "taskId": "5c79****be8e",
  "callBackUrl": "https://example.callback",
  "audioId": "8ca376e7-******-08aaf2c6dd27"
}
'
{
  "code": 200,
  "msg": "success",
  "data": {
    "taskId": "5c79****be8e"
  }
}

​
Usage Guide

  • Convert separated audio tracks into structured MIDI data containing pitch, timing, and velocity information
  • Requires a completed vocal separation task ID (from the Vocal Removal API)
  • Generates MIDI note data for multiple detected instruments including drums, bass, guitar, keyboards, and more
  • Ideal for music transcription, notation, remixing, or educational analysis
  • Best results on clean, well-separated audio tracks with clear instrument parts

​
Prerequisites

You must first use the Vocal & Instrument Stem Separation API to separate your audio before generating MIDI.

​
Parameter Reference

NameTypeDescription
taskIdstringRequired. Task ID from a completed vocal separation
callBackUrlstringRequired. URL to receive MIDI generation completion notifications
audioIdstringOptional. Specifies which separated audio track to generate MIDI from. This audioId can be obtained from the originData array in the Get Vocal Separation Details endpoint response. Each item in originData contains an id field that can be used here. If not provided, MIDI will be generated from all separated tracks.

​
Developer Notes

  • The callback will contain detailed note data for each detected instrument
  • Each note includes: pitch (MIDI note number), start (seconds), end (seconds), velocity (0-1)
  • Not all instruments may be detected - depends on audio content
  • Billing: Check current per-call credit costs at https://api.box/billing

Authorizations

​
Authorization
string
header
required

🔑 API Authentication

All endpoints require authentication using Bearer Token.

Get API Key

  1. Visit the API Key Management Page to obtain your API Key

Usage

Add to request headers:

Authorization: Bearer YOUR_API_KEY

⚠️ Note:

  • Keep your API Key secure and do not share it with others
  • If you suspect your API Key has been compromised, reset it immediately from the management page

Body

application/json
​
taskId
string
required

Task ID from a completed vocal separation. This should be the taskId returned from the Vocal & Instrument Stem Separation endpoint.

Example:

"5c79****be8e"

​
callBackUrl
string<uri>
required

The URL to receive MIDI generation task completion updates. Required for all MIDI generation requests.

  • System will POST task status and MIDI note data to this URL when generation completes
  • Callback includes detailed note information for each detected instrument with pitch, timing, and velocity
  • Your callback endpoint should accept POST requests with JSON payload containing MIDI data
  • For detailed callback format and implementation guide, see MIDI Generation Callbacks
  • Alternatively, use the Get MIDI Generation Details endpoint to poll task status
Example:

"https://example.callback"

​
audioId
string

Optional. Specifies which separated audio track to generate MIDI from. This audioId can be obtained from the originData array in the Get Vocal Separation Details endpoint response. Each item in originData contains an id field that can be used here. If not provided, MIDI will be generated from all separated tracks.

Example:

"8ca376e7-******-08aaf2c6dd27"

Response

MIDI generation task created successfully

​
code
integer

Response status code

Example:

200

​
msg
string

Response message

Example:

"success"

​
data
object

Response data containing task information